The present invention relates generally to a cooling water pump and more particularly to a cooling water pump for use on the pump housing of an internal combustion engine.
Such a cooling water pump is disclosed in DE-PS 22 55 017. This reference discloses a pump in which the impeller is open axially in the direction of the pump housing. The bearing cover, which is structured like a flange, is sealed with respect to the pump housing by a flexible flange gasket. The output capacity that can actually be achieved is to high degree dependent on the precision of the gap between the impeller and the pump housing, which is a function of the production technology. The output capacity is also dependent on the coverage of the impeller by the pump housing, in the case of adjustable pumps, and can therefore vary to a significant degree.
Thus, one limitation of the prior art is that there is no cooling water pump that can be manufactured in such a manner as to result in a precise output capacity that can be predetermined.